Section 22.3 (Exam 3)

Question 1

What are the two types of speciation?

Answer 1

Allopatric and sympatric

Question 2

Define allopatric speciation.

Answer 2

Populations are separated by a physical barrier

Question 3

Define sympatric speciation.

Answer 3

Speciation without physical isolation

Question 4

After allopatric speciation occurs, how are the two new species related to each other?

Answer 4

They are often sister species

Question 5

Darwin’s finches are an example of what type of speciation?

Answer 5

allopatric

Question 6

Which of the three types of selection can lead to sympatric speciation?

Answer 6

disruptive selection

Question 7

What is the most common way sympatric speciation occurs?

Answer 7

polyploidy

Question 8

Define polyploidy.

Answer 8

duplication of whole sets of chromosomes

Question 9

What are the two types of polyploidy?

Answer 9

autopolyploidy and allopolyploidy

Question 10

Define autopolyploidy.

Answer 10

chromosome duplication in a single species

Question 11

Define allopolyploidy.

Answer 11

Combining chromosomes from two species

Question 12

Why is polyploidy important in plant evolution?

Answer 12

Increased genetic diversity from more genetic material

Reproductive isolation leads to speciation

Question 13

How does autopolyploidy occur accidentally?

Answer 13

if two diploid gametes combine

Question 14

What is the result of autopolyploidy after two diploid gametes combine?

Answer 14

A tetraploid individual

Question 15

What is yielded if a tetraploid and a diploid mate?

Answer 15

A sterile triploid

Question 16

How could a tetraploid individual speciate?

Answer 16

Self-fertilization or mating with another tetraploid

Question 17

Why can autopolyploidy cause speciation so quickly?

Answer 17

Once a tetraploid individual is formed, all it has to do is mate with another tetraploid, and a whole new species is formed.

Complete reproductive isolation within two generations